This invention relates to the manufacture of data storage devices such as magnetically and optically written discs. Examples are hard and floppy magnetic discs as used in personal computers where the data is written in magnetically as well as CD ROMs which normally have data written in optically, i.e. usually by laser beam.
The invention relates specifically to the stage of manufacture of the storage device where indexed tracks or sectors are created. These are necessary so that the data recording and reproducing systems can identify the location of data put into and read out from the storage device. Moreover for high quality performance these indexed tracks or sectors have to be very accurately provided on the storage device.
This manufacture involves separate stages wherein the media is examined (certified) and written to (servo written). Current practice requires separate discrete pieces of equipment to perform these tasks at separate stages of manufacture.
The tasks all require the rotation of the media disc with extreme quality of motion while magnetic or other heads and sensors are moved across the surface with controlled motion, positional relationships and geometry. In this regard there are normally two separate units, one of which, generally referred to as a servo-writer writes the sectors to the disc, and the other, generally referred to as a verifier, verifies the surface(s) of the disc, usually optically.
The aim of this invention is to provide a particularly accurate and simple arrangement for performing these tasks, and accordingly the invention provides a single platform with the ability to carry all the systems required to perform these tasks, particularly to both verify the surface and write the sectors, at one stage within the manufacturing process.
Accordingly one aspect of the invention comprises a single monolithic support platform, a rotary carrier arranged for rotation of a media disc supported on said platform, a write head arranged for substantially radial movement relative to said carrier and for servo writing of data to said media disc and a certifier head arranged for substantially radial movement relative to said carrier and for verification of the media disc.
For the ultimate in quality of motion some or preferable all such motion systems should be carried on air bearings. In a preferred construction the mountings for all of these air-bearing systems should be a single and solid component incorporating the maximum rigidity providing a common datum for each discrete process.
Accordingly a preferred form of the present invention utilises a single body to carry all the air bearing systems required to perform all the processes needed for the media to be installed in a disc drive or other data storage device. All motion systems thus contained can then be capable of simultaneous operation.
Respective drive means are typically provided for driving each of the moving components, namely, the rotary carrier, the write head and certifier head. One or more of the drive means may comprise an integrated motor which is arranged for directly driving a rotary spindle, or other member, supporting the respective component. Providing integrated drive means eases manufacture and alignment of the constituent parts of the device.
One or more of the drive means may be an indirect drive means comprising a motor which is mounted independently of the respective component, and coupling means for transferring the drive to the respective component whilst minimising the transmission of any undesirable vibration. In some embodiments, the coupling means may be a resilient coupling means disposed in substantially axial alignment with a rotary spindle of the respective component. In other embodiments, the coupling means may comprise a drive belt.
It is particularly preferred that indirect drive means are provided for driving the rotary carrier carrying the media disc. The use of indirect drive means can allow substantial mechanical isolation of the motor from sensitive parts of the device. In particular, the indirect drive can help to prevent harmful vibrations being transmitted to the media disc or the servowriter head, which might otherwise cause track errors.
According to another aspect of the invention there is provided a method of preparing media storage discs comprising the steps of mounting a media disc on a rotary carrier supported on a platform, verifying the integrity of the mounted media disc using a certifier head and servowriting data to the mounted media disc with the write head without removing the media disc from the rotary carrier between the verifying and servowriting steps.
According to yet another aspect of the invention there is provided a device for preparation of a media storage disc comprising a single monolithic support platform, a rotary carrier arranged for rotation of a media disc supported on said platform, a write head arranged for substantially radial movement relative to said carrier and for servo writing of data to said media disc, a certifier head arranged for substantially radial movement relative to said carrier and for confirming the integrity of the medium of the disc and indirect drive means for driving the rotary carrier, the drive means comprising a motor mounted independently of the rotary carrier, and coupling means for transmitting the drive to the rotary carrier whilst minimizing the transmission of any undesirable vibration.